1// SPDX-License-Identifier: GPL-2.0 2/* 3 * Copyright (C) 2018-2020 Intel Corporation. 4 * Copyright (C) 2020 Red Hat, Inc. 5 * 6 * Author: Tiwei Bie <tiwei.bie@intel.com> 7 * Jason Wang <jasowang@redhat.com> 8 * 9 * Thanks Michael S. Tsirkin for the valuable comments and 10 * suggestions. And thanks to Cunming Liang and Zhihong Wang for all 11 * their supports. 12 */ 13 14#include <linux/kernel.h> 15#include <linux/module.h> 16#include <linux/cdev.h> 17#include <linux/device.h> 18#include <linux/mm.h> 19#include <linux/iommu.h> 20#include <linux/uuid.h> 21#include <linux/vdpa.h> 22#include <linux/nospec.h> 23#include <linux/vhost.h> 24#include <linux/virtio_net.h> 25 26#include "vhost.h" 27 28enum { 29 VHOST_VDPA_BACKEND_FEATURES = 30 (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2) | 31 (1ULL << VHOST_BACKEND_F_IOTLB_BATCH), 32}; 33 34#define VHOST_VDPA_DEV_MAX (1U << MINORBITS) 35 36struct vhost_vdpa { 37 struct vhost_dev vdev; 38 struct iommu_domain *domain; 39 struct vhost_virtqueue *vqs; 40 struct completion completion; 41 struct vdpa_device *vdpa; 42 struct device dev; 43 struct cdev cdev; 44 atomic_t opened; 45 int nvqs; 46 int virtio_id; 47 int minor; 48 struct eventfd_ctx *config_ctx; 49 int in_batch; 50 struct vdpa_iova_range range; 51}; 52 53static DEFINE_IDA(vhost_vdpa_ida); 54 55static dev_t vhost_vdpa_major; 56 57static void handle_vq_kick(struct vhost_work *work) 58{ 59 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, 60 poll.work); 61 struct vhost_vdpa *v = container_of(vq->dev, struct vhost_vdpa, vdev); 62 const struct vdpa_config_ops *ops = v->vdpa->config; 63 64 ops->kick_vq(v->vdpa, vq - v->vqs); 65} 66 67static irqreturn_t vhost_vdpa_virtqueue_cb(void *private) 68{ 69 struct vhost_virtqueue *vq = private; 70 struct eventfd_ctx *call_ctx = vq->call_ctx.ctx; 71 72 if (call_ctx) 73 eventfd_signal(call_ctx, 1); 74 75 return IRQ_HANDLED; 76} 77 78static irqreturn_t vhost_vdpa_config_cb(void *private) 79{ 80 struct vhost_vdpa *v = private; 81 struct eventfd_ctx *config_ctx = v->config_ctx; 82 83 if (config_ctx) 84 eventfd_signal(config_ctx, 1); 85 86 return IRQ_HANDLED; 87} 88 89static void vhost_vdpa_setup_vq_irq(struct vhost_vdpa *v, u16 qid) 90{ 91 struct vhost_virtqueue *vq = &v->vqs[qid]; 92 const struct vdpa_config_ops *ops = v->vdpa->config; 93 struct vdpa_device *vdpa = v->vdpa; 94 int ret, irq; 95 96 if (!ops->get_vq_irq) 97 return; 98 99 irq = ops->get_vq_irq(vdpa, qid); 100 if (irq < 0) 101 return; 102 103 irq_bypass_unregister_producer(&vq->call_ctx.producer); 104 if (!vq->call_ctx.ctx) 105 return; 106 107 vq->call_ctx.producer.token = vq->call_ctx.ctx; 108 vq->call_ctx.producer.irq = irq; 109 ret = irq_bypass_register_producer(&vq->call_ctx.producer); 110 if (unlikely(ret)) 111 dev_info(&v->dev, "vq %u, irq bypass producer (token %p) registration fails, ret = %d\n", 112 qid, vq->call_ctx.producer.token, ret); 113} 114 115static void vhost_vdpa_unsetup_vq_irq(struct vhost_vdpa *v, u16 qid) 116{ 117 struct vhost_virtqueue *vq = &v->vqs[qid]; 118 119 irq_bypass_unregister_producer(&vq->call_ctx.producer); 120} 121 122static void vhost_vdpa_reset(struct vhost_vdpa *v) 123{ 124 struct vdpa_device *vdpa = v->vdpa; 125 126 vdpa_reset(vdpa); 127 v->in_batch = 0; 128} 129 130static long vhost_vdpa_get_device_id(struct vhost_vdpa *v, u8 __user *argp) 131{ 132 struct vdpa_device *vdpa = v->vdpa; 133 const struct vdpa_config_ops *ops = vdpa->config; 134 u32 device_id; 135 136 device_id = ops->get_device_id(vdpa); 137 138 if (copy_to_user(argp, &device_id, sizeof(device_id))) 139 return -EFAULT; 140 141 return 0; 142} 143 144static long vhost_vdpa_get_status(struct vhost_vdpa *v, u8 __user *statusp) 145{ 146 struct vdpa_device *vdpa = v->vdpa; 147 const struct vdpa_config_ops *ops = vdpa->config; 148 u8 status; 149 150 status = ops->get_status(vdpa); 151 152 if (copy_to_user(statusp, &status, sizeof(status))) 153 return -EFAULT; 154 155 return 0; 156} 157 158static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp) 159{ 160 struct vdpa_device *vdpa = v->vdpa; 161 const struct vdpa_config_ops *ops = vdpa->config; 162 u8 status, status_old; 163 int nvqs = v->nvqs; 164 u16 i; 165 166 if (copy_from_user(&status, statusp, sizeof(status))) 167 return -EFAULT; 168 169 status_old = ops->get_status(vdpa); 170 171 /* 172 * Userspace shouldn't remove status bits unless reset the 173 * status to 0. 174 */ 175 if (status != 0 && (ops->get_status(vdpa) & ~status) != 0) 176 return -EINVAL; 177 178 ops->set_status(vdpa, status); 179 180 if ((status & VIRTIO_CONFIG_S_DRIVER_OK) && !(status_old & VIRTIO_CONFIG_S_DRIVER_OK)) 181 for (i = 0; i < nvqs; i++) 182 vhost_vdpa_setup_vq_irq(v, i); 183 184 if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK)) 185 for (i = 0; i < nvqs; i++) 186 vhost_vdpa_unsetup_vq_irq(v, i); 187 188 return 0; 189} 190 191static int vhost_vdpa_config_validate(struct vhost_vdpa *v, 192 struct vhost_vdpa_config *c) 193{ 194 long size = 0; 195 196 switch (v->virtio_id) { 197 case VIRTIO_ID_NET: 198 size = sizeof(struct virtio_net_config); 199 break; 200 } 201 202 if (c->len == 0 || c->off > size) 203 return -EINVAL; 204 205 if (c->len > size - c->off) 206 return -E2BIG; 207 208 return 0; 209} 210 211static long vhost_vdpa_get_config(struct vhost_vdpa *v, 212 struct vhost_vdpa_config __user *c) 213{ 214 struct vdpa_device *vdpa = v->vdpa; 215 struct vhost_vdpa_config config; 216 unsigned long size = offsetof(struct vhost_vdpa_config, buf); 217 u8 *buf; 218 219 if (copy_from_user(&config, c, size)) 220 return -EFAULT; 221 if (vhost_vdpa_config_validate(v, &config)) 222 return -EINVAL; 223 buf = kvzalloc(config.len, GFP_KERNEL); 224 if (!buf) 225 return -ENOMEM; 226 227 vdpa_get_config(vdpa, config.off, buf, config.len); 228 229 if (copy_to_user(c->buf, buf, config.len)) { 230 kvfree(buf); 231 return -EFAULT; 232 } 233 234 kvfree(buf); 235 return 0; 236} 237 238static long vhost_vdpa_set_config(struct vhost_vdpa *v, 239 struct vhost_vdpa_config __user *c) 240{ 241 struct vdpa_device *vdpa = v->vdpa; 242 const struct vdpa_config_ops *ops = vdpa->config; 243 struct vhost_vdpa_config config; 244 unsigned long size = offsetof(struct vhost_vdpa_config, buf); 245 u8 *buf; 246 247 if (copy_from_user(&config, c, size)) 248 return -EFAULT; 249 if (vhost_vdpa_config_validate(v, &config)) 250 return -EINVAL; 251 buf = kvzalloc(config.len, GFP_KERNEL); 252 if (!buf) 253 return -ENOMEM; 254 255 if (copy_from_user(buf, c->buf, config.len)) { 256 kvfree(buf); 257 return -EFAULT; 258 } 259 260 ops->set_config(vdpa, config.off, buf, config.len); 261 262 kvfree(buf); 263 return 0; 264} 265 266static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep) 267{ 268 struct vdpa_device *vdpa = v->vdpa; 269 const struct vdpa_config_ops *ops = vdpa->config; 270 u64 features; 271 272 features = ops->get_features(vdpa); 273 274 if (copy_to_user(featurep, &features, sizeof(features))) 275 return -EFAULT; 276 277 return 0; 278} 279 280static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep) 281{ 282 struct vdpa_device *vdpa = v->vdpa; 283 const struct vdpa_config_ops *ops = vdpa->config; 284 u64 features; 285 286 /* 287 * It's not allowed to change the features after they have 288 * been negotiated. 289 */ 290 if (ops->get_status(vdpa) & VIRTIO_CONFIG_S_FEATURES_OK) 291 return -EBUSY; 292 293 if (copy_from_user(&features, featurep, sizeof(features))) 294 return -EFAULT; 295 296 if (vdpa_set_features(vdpa, features)) 297 return -EINVAL; 298 299 return 0; 300} 301 302static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp) 303{ 304 struct vdpa_device *vdpa = v->vdpa; 305 const struct vdpa_config_ops *ops = vdpa->config; 306 u16 num; 307 308 num = ops->get_vq_num_max(vdpa); 309 310 if (copy_to_user(argp, &num, sizeof(num))) 311 return -EFAULT; 312 313 return 0; 314} 315 316static void vhost_vdpa_config_put(struct vhost_vdpa *v) 317{ 318 if (v->config_ctx) { 319 eventfd_ctx_put(v->config_ctx); 320 v->config_ctx = NULL; 321 } 322} 323 324static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp) 325{ 326 struct vdpa_callback cb; 327 int fd; 328 struct eventfd_ctx *ctx; 329 330 cb.callback = vhost_vdpa_config_cb; 331 cb.private = v; 332 if (copy_from_user(&fd, argp, sizeof(fd))) 333 return -EFAULT; 334 335 ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd); 336 swap(ctx, v->config_ctx); 337 338 if (!IS_ERR_OR_NULL(ctx)) 339 eventfd_ctx_put(ctx); 340 341 if (IS_ERR(v->config_ctx)) { 342 long ret = PTR_ERR(v->config_ctx); 343 344 v->config_ctx = NULL; 345 return ret; 346 } 347 348 v->vdpa->config->set_config_cb(v->vdpa, &cb); 349 350 return 0; 351} 352 353static long vhost_vdpa_get_iova_range(struct vhost_vdpa *v, u32 __user *argp) 354{ 355 struct vhost_vdpa_iova_range range = { 356 .first = v->range.first, 357 .last = v->range.last, 358 }; 359 360 if (copy_to_user(argp, &range, sizeof(range))) 361 return -EFAULT; 362 return 0; 363} 364 365static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd, 366 void __user *argp) 367{ 368 struct vdpa_device *vdpa = v->vdpa; 369 const struct vdpa_config_ops *ops = vdpa->config; 370 struct vdpa_vq_state vq_state; 371 struct vdpa_callback cb; 372 struct vhost_virtqueue *vq; 373 struct vhost_vring_state s; 374 u32 idx; 375 long r; 376 377 r = get_user(idx, (u32 __user *)argp); 378 if (r < 0) 379 return r; 380 381 if (idx >= v->nvqs) 382 return -ENOBUFS; 383 384 idx = array_index_nospec(idx, v->nvqs); 385 vq = &v->vqs[idx]; 386 387 switch (cmd) { 388 case VHOST_VDPA_SET_VRING_ENABLE: 389 if (copy_from_user(&s, argp, sizeof(s))) 390 return -EFAULT; 391 ops->set_vq_ready(vdpa, idx, s.num); 392 return 0; 393 case VHOST_GET_VRING_BASE: 394 r = ops->get_vq_state(v->vdpa, idx, &vq_state); 395 if (r) 396 return r; 397 398 vq->last_avail_idx = vq_state.avail_index; 399 break; 400 } 401 402 r = vhost_vring_ioctl(&v->vdev, cmd, argp); 403 if (r) 404 return r; 405 406 switch (cmd) { 407 case VHOST_SET_VRING_ADDR: 408 if (ops->set_vq_address(vdpa, idx, 409 (u64)(uintptr_t)vq->desc, 410 (u64)(uintptr_t)vq->avail, 411 (u64)(uintptr_t)vq->used)) 412 r = -EINVAL; 413 break; 414 415 case VHOST_SET_VRING_BASE: 416 vq_state.avail_index = vq->last_avail_idx; 417 if (ops->set_vq_state(vdpa, idx, &vq_state)) 418 r = -EINVAL; 419 break; 420 421 case VHOST_SET_VRING_CALL: 422 if (vq->call_ctx.ctx) { 423 cb.callback = vhost_vdpa_virtqueue_cb; 424 cb.private = vq; 425 } else { 426 cb.callback = NULL; 427 cb.private = NULL; 428 } 429 ops->set_vq_cb(vdpa, idx, &cb); 430 vhost_vdpa_setup_vq_irq(v, idx); 431 break; 432 433 case VHOST_SET_VRING_NUM: 434 ops->set_vq_num(vdpa, idx, vq->num); 435 break; 436 } 437 438 return r; 439} 440 441static long vhost_vdpa_unlocked_ioctl(struct file *filep, 442 unsigned int cmd, unsigned long arg) 443{ 444 struct vhost_vdpa *v = filep->private_data; 445 struct vhost_dev *d = &v->vdev; 446 void __user *argp = (void __user *)arg; 447 u64 __user *featurep = argp; 448 u64 features; 449 long r = 0; 450 451 if (cmd == VHOST_SET_BACKEND_FEATURES) { 452 if (copy_from_user(&features, featurep, sizeof(features))) 453 return -EFAULT; 454 if (features & ~VHOST_VDPA_BACKEND_FEATURES) 455 return -EOPNOTSUPP; 456 vhost_set_backend_features(&v->vdev, features); 457 return 0; 458 } 459 460 mutex_lock(&d->mutex); 461 462 switch (cmd) { 463 case VHOST_VDPA_GET_DEVICE_ID: 464 r = vhost_vdpa_get_device_id(v, argp); 465 break; 466 case VHOST_VDPA_GET_STATUS: 467 r = vhost_vdpa_get_status(v, argp); 468 break; 469 case VHOST_VDPA_SET_STATUS: 470 r = vhost_vdpa_set_status(v, argp); 471 break; 472 case VHOST_VDPA_GET_CONFIG: 473 r = vhost_vdpa_get_config(v, argp); 474 break; 475 case VHOST_VDPA_SET_CONFIG: 476 r = vhost_vdpa_set_config(v, argp); 477 break; 478 case VHOST_GET_FEATURES: 479 r = vhost_vdpa_get_features(v, argp); 480 break; 481 case VHOST_SET_FEATURES: 482 r = vhost_vdpa_set_features(v, argp); 483 break; 484 case VHOST_VDPA_GET_VRING_NUM: 485 r = vhost_vdpa_get_vring_num(v, argp); 486 break; 487 case VHOST_SET_LOG_BASE: 488 case VHOST_SET_LOG_FD: 489 r = -ENOIOCTLCMD; 490 break; 491 case VHOST_VDPA_SET_CONFIG_CALL: 492 r = vhost_vdpa_set_config_call(v, argp); 493 break; 494 case VHOST_GET_BACKEND_FEATURES: 495 features = VHOST_VDPA_BACKEND_FEATURES; 496 if (copy_to_user(featurep, &features, sizeof(features))) 497 r = -EFAULT; 498 break; 499 case VHOST_VDPA_GET_IOVA_RANGE: 500 r = vhost_vdpa_get_iova_range(v, argp); 501 break; 502 default: 503 r = vhost_dev_ioctl(&v->vdev, cmd, argp); 504 if (r == -ENOIOCTLCMD) 505 r = vhost_vdpa_vring_ioctl(v, cmd, argp); 506 break; 507 } 508 509 mutex_unlock(&d->mutex); 510 return r; 511} 512 513static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last) 514{ 515 struct vhost_dev *dev = &v->vdev; 516 struct vhost_iotlb *iotlb = dev->iotlb; 517 struct vhost_iotlb_map *map; 518 struct page *page; 519 unsigned long pfn, pinned; 520 521 while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) { 522 pinned = map->size >> PAGE_SHIFT; 523 for (pfn = map->addr >> PAGE_SHIFT; 524 pinned > 0; pfn++, pinned--) { 525 page = pfn_to_page(pfn); 526 if (map->perm & VHOST_ACCESS_WO) 527 set_page_dirty_lock(page); 528 unpin_user_page(page); 529 } 530 atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm); 531 vhost_iotlb_map_free(iotlb, map); 532 } 533} 534 535static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v) 536{ 537 struct vhost_dev *dev = &v->vdev; 538 539 vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1); 540 kfree(dev->iotlb); 541 dev->iotlb = NULL; 542} 543 544static int perm_to_iommu_flags(u32 perm) 545{ 546 int flags = 0; 547 548 switch (perm) { 549 case VHOST_ACCESS_WO: 550 flags |= IOMMU_WRITE; 551 break; 552 case VHOST_ACCESS_RO: 553 flags |= IOMMU_READ; 554 break; 555 case VHOST_ACCESS_RW: 556 flags |= (IOMMU_WRITE | IOMMU_READ); 557 break; 558 default: 559 WARN(1, "invalidate vhost IOTLB permission\n"); 560 break; 561 } 562 563 return flags | IOMMU_CACHE; 564} 565 566static int vhost_vdpa_map(struct vhost_vdpa *v, 567 u64 iova, u64 size, u64 pa, u32 perm) 568{ 569 struct vhost_dev *dev = &v->vdev; 570 struct vdpa_device *vdpa = v->vdpa; 571 const struct vdpa_config_ops *ops = vdpa->config; 572 int r = 0; 573 574 r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1, 575 pa, perm); 576 if (r) 577 return r; 578 579 if (ops->dma_map) { 580 r = ops->dma_map(vdpa, iova, size, pa, perm); 581 } else if (ops->set_map) { 582 if (!v->in_batch) 583 r = ops->set_map(vdpa, dev->iotlb); 584 } else { 585 r = iommu_map(v->domain, iova, pa, size, 586 perm_to_iommu_flags(perm)); 587 } 588 589 if (r) 590 vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1); 591 else 592 atomic64_add(size >> PAGE_SHIFT, &dev->mm->pinned_vm); 593 594 return r; 595} 596 597static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size) 598{ 599 struct vhost_dev *dev = &v->vdev; 600 struct vdpa_device *vdpa = v->vdpa; 601 const struct vdpa_config_ops *ops = vdpa->config; 602 603 vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1); 604 605 if (ops->dma_map) { 606 ops->dma_unmap(vdpa, iova, size); 607 } else if (ops->set_map) { 608 if (!v->in_batch) 609 ops->set_map(vdpa, dev->iotlb); 610 } else { 611 iommu_unmap(v->domain, iova, size); 612 } 613} 614 615static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, 616 struct vhost_iotlb_msg *msg) 617{ 618 struct vhost_dev *dev = &v->vdev; 619 struct vhost_iotlb *iotlb = dev->iotlb; 620 struct page **page_list; 621 unsigned long list_size = PAGE_SIZE / sizeof(struct page *); 622 unsigned int gup_flags = FOLL_LONGTERM; 623 unsigned long npages, cur_base, map_pfn, last_pfn = 0; 624 unsigned long lock_limit, sz2pin, nchunks, i; 625 u64 iova = msg->iova; 626 long pinned; 627 int ret = 0; 628 629 if (msg->iova < v->range.first || !msg->size || 630 msg->iova > U64_MAX - msg->size + 1 || 631 msg->iova + msg->size - 1 > v->range.last) 632 return -EINVAL; 633 634 if (vhost_iotlb_itree_first(iotlb, msg->iova, 635 msg->iova + msg->size - 1)) 636 return -EEXIST; 637 638 /* Limit the use of memory for bookkeeping */ 639 page_list = (struct page **) __get_free_page(GFP_KERNEL); 640 if (!page_list) 641 return -ENOMEM; 642 643 if (msg->perm & VHOST_ACCESS_WO) 644 gup_flags |= FOLL_WRITE; 645 646 npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT; 647 if (!npages) { 648 ret = -EINVAL; 649 goto free; 650 } 651 652 mmap_read_lock(dev->mm); 653 654 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 655 if (npages + atomic64_read(&dev->mm->pinned_vm) > lock_limit) { 656 ret = -ENOMEM; 657 goto unlock; 658 } 659 660 cur_base = msg->uaddr & PAGE_MASK; 661 iova &= PAGE_MASK; 662 nchunks = 0; 663 664 while (npages) { 665 sz2pin = min_t(unsigned long, npages, list_size); 666 pinned = pin_user_pages(cur_base, sz2pin, 667 gup_flags, page_list, NULL); 668 if (sz2pin != pinned) { 669 if (pinned < 0) { 670 ret = pinned; 671 } else { 672 unpin_user_pages(page_list, pinned); 673 ret = -ENOMEM; 674 } 675 goto out; 676 } 677 nchunks++; 678 679 if (!last_pfn) 680 map_pfn = page_to_pfn(page_list[0]); 681 682 for (i = 0; i < pinned; i++) { 683 unsigned long this_pfn = page_to_pfn(page_list[i]); 684 u64 csize; 685 686 if (last_pfn && (this_pfn != last_pfn + 1)) { 687 /* Pin a contiguous chunk of memory */ 688 csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT; 689 ret = vhost_vdpa_map(v, iova, csize, 690 map_pfn << PAGE_SHIFT, 691 msg->perm); 692 if (ret) { 693 /* 694 * Unpin the pages that are left unmapped 695 * from this point on in the current 696 * page_list. The remaining outstanding 697 * ones which may stride across several 698 * chunks will be covered in the common 699 * error path subsequently. 700 */ 701 unpin_user_pages(&page_list[i], 702 pinned - i); 703 goto out; 704 } 705 706 map_pfn = this_pfn; 707 iova += csize; 708 nchunks = 0; 709 } 710 711 last_pfn = this_pfn; 712 } 713 714 cur_base += pinned << PAGE_SHIFT; 715 npages -= pinned; 716 } 717 718 /* Pin the rest chunk */ 719 ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT, 720 map_pfn << PAGE_SHIFT, msg->perm); 721out: 722 if (ret) { 723 if (nchunks) { 724 unsigned long pfn; 725 726 /* 727 * Unpin the outstanding pages which are yet to be 728 * mapped but haven't due to vdpa_map() or 729 * pin_user_pages() failure. 730 * 731 * Mapped pages are accounted in vdpa_map(), hence 732 * the corresponding unpinning will be handled by 733 * vdpa_unmap(). 734 */ 735 WARN_ON(!last_pfn); 736 for (pfn = map_pfn; pfn <= last_pfn; pfn++) 737 unpin_user_page(pfn_to_page(pfn)); 738 } 739 vhost_vdpa_unmap(v, msg->iova, msg->size); 740 } 741unlock: 742 mmap_read_unlock(dev->mm); 743free: 744 free_page((unsigned long)page_list); 745 return ret; 746} 747 748static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev, 749 struct vhost_iotlb_msg *msg) 750{ 751 struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev); 752 struct vdpa_device *vdpa = v->vdpa; 753 const struct vdpa_config_ops *ops = vdpa->config; 754 int r = 0; 755 756 mutex_lock(&dev->mutex); 757 758 r = vhost_dev_check_owner(dev); 759 if (r) 760 goto unlock; 761 762 switch (msg->type) { 763 case VHOST_IOTLB_UPDATE: 764 r = vhost_vdpa_process_iotlb_update(v, msg); 765 break; 766 case VHOST_IOTLB_INVALIDATE: 767 vhost_vdpa_unmap(v, msg->iova, msg->size); 768 break; 769 case VHOST_IOTLB_BATCH_BEGIN: 770 v->in_batch = true; 771 break; 772 case VHOST_IOTLB_BATCH_END: 773 if (v->in_batch && ops->set_map) 774 ops->set_map(vdpa, dev->iotlb); 775 v->in_batch = false; 776 break; 777 default: 778 r = -EINVAL; 779 break; 780 } 781unlock: 782 mutex_unlock(&dev->mutex); 783 784 return r; 785} 786 787static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb, 788 struct iov_iter *from) 789{ 790 struct file *file = iocb->ki_filp; 791 struct vhost_vdpa *v = file->private_data; 792 struct vhost_dev *dev = &v->vdev; 793 794 return vhost_chr_write_iter(dev, from); 795} 796 797static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v) 798{ 799 struct vdpa_device *vdpa = v->vdpa; 800 const struct vdpa_config_ops *ops = vdpa->config; 801 struct device *dma_dev = vdpa_get_dma_dev(vdpa); 802 struct bus_type *bus; 803 int ret; 804 805 /* Device want to do DMA by itself */ 806 if (ops->set_map || ops->dma_map) 807 return 0; 808 809 bus = dma_dev->bus; 810 if (!bus) 811 return -EFAULT; 812 813 if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY)) 814 return -ENOTSUPP; 815 816 v->domain = iommu_domain_alloc(bus); 817 if (!v->domain) 818 return -EIO; 819 820 ret = iommu_attach_device(v->domain, dma_dev); 821 if (ret) 822 goto err_attach; 823 824 return 0; 825 826err_attach: 827 iommu_domain_free(v->domain); 828 return ret; 829} 830 831static void vhost_vdpa_free_domain(struct vhost_vdpa *v) 832{ 833 struct vdpa_device *vdpa = v->vdpa; 834 struct device *dma_dev = vdpa_get_dma_dev(vdpa); 835 836 if (v->domain) { 837 iommu_detach_device(v->domain, dma_dev); 838 iommu_domain_free(v->domain); 839 } 840 841 v->domain = NULL; 842} 843 844static void vhost_vdpa_set_iova_range(struct vhost_vdpa *v) 845{ 846 struct vdpa_iova_range *range = &v->range; 847 struct iommu_domain_geometry geo; 848 struct vdpa_device *vdpa = v->vdpa; 849 const struct vdpa_config_ops *ops = vdpa->config; 850 851 if (ops->get_iova_range) { 852 *range = ops->get_iova_range(vdpa); 853 } else if (v->domain && 854 !iommu_domain_get_attr(v->domain, 855 DOMAIN_ATTR_GEOMETRY, &geo) && 856 geo.force_aperture) { 857 range->first = geo.aperture_start; 858 range->last = geo.aperture_end; 859 } else { 860 range->first = 0; 861 range->last = ULLONG_MAX; 862 } 863} 864 865static int vhost_vdpa_open(struct inode *inode, struct file *filep) 866{ 867 struct vhost_vdpa *v; 868 struct vhost_dev *dev; 869 struct vhost_virtqueue **vqs; 870 int nvqs, i, r, opened; 871 872 v = container_of(inode->i_cdev, struct vhost_vdpa, cdev); 873 874 opened = atomic_cmpxchg(&v->opened, 0, 1); 875 if (opened) 876 return -EBUSY; 877 878 nvqs = v->nvqs; 879 vhost_vdpa_reset(v); 880 881 vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL); 882 if (!vqs) { 883 r = -ENOMEM; 884 goto err; 885 } 886 887 dev = &v->vdev; 888 for (i = 0; i < nvqs; i++) { 889 vqs[i] = &v->vqs[i]; 890 vqs[i]->handle_kick = handle_vq_kick; 891 } 892 vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false, 893 vhost_vdpa_process_iotlb_msg); 894 895 dev->iotlb = vhost_iotlb_alloc(0, 0); 896 if (!dev->iotlb) { 897 r = -ENOMEM; 898 goto err_init_iotlb; 899 } 900 901 r = vhost_vdpa_alloc_domain(v); 902 if (r) 903 goto err_init_iotlb; 904 905 vhost_vdpa_set_iova_range(v); 906 907 filep->private_data = v; 908 909 return 0; 910 911err_init_iotlb: 912 vhost_dev_cleanup(&v->vdev); 913 kfree(vqs); 914err: 915 atomic_dec(&v->opened); 916 return r; 917} 918 919static void vhost_vdpa_clean_irq(struct vhost_vdpa *v) 920{ 921 int i; 922 923 for (i = 0; i < v->nvqs; i++) 924 vhost_vdpa_unsetup_vq_irq(v, i); 925} 926 927static int vhost_vdpa_release(struct inode *inode, struct file *filep) 928{ 929 struct vhost_vdpa *v = filep->private_data; 930 struct vhost_dev *d = &v->vdev; 931 932 mutex_lock(&d->mutex); 933 filep->private_data = NULL; 934 vhost_vdpa_reset(v); 935 vhost_dev_stop(&v->vdev); 936 vhost_vdpa_iotlb_free(v); 937 vhost_vdpa_free_domain(v); 938 vhost_vdpa_config_put(v); 939 vhost_vdpa_clean_irq(v); 940 vhost_dev_cleanup(&v->vdev); 941 kfree(v->vdev.vqs); 942 mutex_unlock(&d->mutex); 943 944 atomic_dec(&v->opened); 945 complete(&v->completion); 946 947 return 0; 948} 949 950#ifdef CONFIG_MMU 951static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf) 952{ 953 struct vhost_vdpa *v = vmf->vma->vm_file->private_data; 954 struct vdpa_device *vdpa = v->vdpa; 955 const struct vdpa_config_ops *ops = vdpa->config; 956 struct vdpa_notification_area notify; 957 struct vm_area_struct *vma = vmf->vma; 958 u16 index = vma->vm_pgoff; 959 960 notify = ops->get_vq_notification(vdpa, index); 961 962 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 963 if (remap_pfn_range(vma, vmf->address & PAGE_MASK, 964 notify.addr >> PAGE_SHIFT, PAGE_SIZE, 965 vma->vm_page_prot)) 966 return VM_FAULT_SIGBUS; 967 968 return VM_FAULT_NOPAGE; 969} 970 971static const struct vm_operations_struct vhost_vdpa_vm_ops = { 972 .fault = vhost_vdpa_fault, 973}; 974 975static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma) 976{ 977 struct vhost_vdpa *v = vma->vm_file->private_data; 978 struct vdpa_device *vdpa = v->vdpa; 979 const struct vdpa_config_ops *ops = vdpa->config; 980 struct vdpa_notification_area notify; 981 unsigned long index = vma->vm_pgoff; 982 983 if (vma->vm_end - vma->vm_start != PAGE_SIZE) 984 return -EINVAL; 985 if ((vma->vm_flags & VM_SHARED) == 0) 986 return -EINVAL; 987 if (vma->vm_flags & VM_READ) 988 return -EINVAL; 989 if (index > 65535) 990 return -EINVAL; 991 if (!ops->get_vq_notification) 992 return -ENOTSUPP; 993 994 /* To be safe and easily modelled by userspace, We only 995 * support the doorbell which sits on the page boundary and 996 * does not share the page with other registers. 997 */ 998 notify = ops->get_vq_notification(vdpa, index); 999 if (notify.addr & (PAGE_SIZE - 1)) 1000 return -EINVAL; 1001 if (vma->vm_end - vma->vm_start != notify.size) 1002 return -ENOTSUPP; 1003 1004 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; 1005 vma->vm_ops = &vhost_vdpa_vm_ops; 1006 return 0; 1007} 1008#endif /* CONFIG_MMU */ 1009 1010static const struct file_operations vhost_vdpa_fops = { 1011 .owner = THIS_MODULE, 1012 .open = vhost_vdpa_open, 1013 .release = vhost_vdpa_release, 1014 .write_iter = vhost_vdpa_chr_write_iter, 1015 .unlocked_ioctl = vhost_vdpa_unlocked_ioctl, 1016#ifdef CONFIG_MMU 1017 .mmap = vhost_vdpa_mmap, 1018#endif /* CONFIG_MMU */ 1019 .compat_ioctl = compat_ptr_ioctl, 1020}; 1021 1022static void vhost_vdpa_release_dev(struct device *device) 1023{ 1024 struct vhost_vdpa *v = 1025 container_of(device, struct vhost_vdpa, dev); 1026 1027 ida_simple_remove(&vhost_vdpa_ida, v->minor); 1028 kfree(v->vqs); 1029 kfree(v); 1030} 1031 1032static int vhost_vdpa_probe(struct vdpa_device *vdpa) 1033{ 1034 const struct vdpa_config_ops *ops = vdpa->config; 1035 struct vhost_vdpa *v; 1036 int minor; 1037 int r; 1038 1039 /* Currently, we only accept the network devices. */ 1040 if (ops->get_device_id(vdpa) != VIRTIO_ID_NET) 1041 return -ENOTSUPP; 1042 1043 v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL); 1044 if (!v) 1045 return -ENOMEM; 1046 1047 minor = ida_simple_get(&vhost_vdpa_ida, 0, 1048 VHOST_VDPA_DEV_MAX, GFP_KERNEL); 1049 if (minor < 0) { 1050 kfree(v); 1051 return minor; 1052 } 1053 1054 atomic_set(&v->opened, 0); 1055 v->minor = minor; 1056 v->vdpa = vdpa; 1057 v->nvqs = vdpa->nvqs; 1058 v->virtio_id = ops->get_device_id(vdpa); 1059 1060 device_initialize(&v->dev); 1061 v->dev.release = vhost_vdpa_release_dev; 1062 v->dev.parent = &vdpa->dev; 1063 v->dev.devt = MKDEV(MAJOR(vhost_vdpa_major), minor); 1064 v->vqs = kmalloc_array(v->nvqs, sizeof(struct vhost_virtqueue), 1065 GFP_KERNEL); 1066 if (!v->vqs) { 1067 r = -ENOMEM; 1068 goto err; 1069 } 1070 1071 r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor); 1072 if (r) 1073 goto err; 1074 1075 cdev_init(&v->cdev, &vhost_vdpa_fops); 1076 v->cdev.owner = THIS_MODULE; 1077 1078 r = cdev_device_add(&v->cdev, &v->dev); 1079 if (r) 1080 goto err; 1081 1082 init_completion(&v->completion); 1083 vdpa_set_drvdata(vdpa, v); 1084 1085 return 0; 1086 1087err: 1088 put_device(&v->dev); 1089 return r; 1090} 1091 1092static void vhost_vdpa_remove(struct vdpa_device *vdpa) 1093{ 1094 struct vhost_vdpa *v = vdpa_get_drvdata(vdpa); 1095 int opened; 1096 1097 cdev_device_del(&v->cdev, &v->dev); 1098 1099 do { 1100 opened = atomic_cmpxchg(&v->opened, 0, 1); 1101 if (!opened) 1102 break; 1103 wait_for_completion(&v->completion); 1104 } while (1); 1105 1106 put_device(&v->dev); 1107} 1108 1109static struct vdpa_driver vhost_vdpa_driver = { 1110 .driver = { 1111 .name = "vhost_vdpa", 1112 }, 1113 .probe = vhost_vdpa_probe, 1114 .remove = vhost_vdpa_remove, 1115}; 1116 1117static int __init vhost_vdpa_init(void) 1118{ 1119 int r; 1120 1121 r = alloc_chrdev_region(&vhost_vdpa_major, 0, VHOST_VDPA_DEV_MAX, 1122 "vhost-vdpa"); 1123 if (r) 1124 goto err_alloc_chrdev; 1125 1126 r = vdpa_register_driver(&vhost_vdpa_driver); 1127 if (r) 1128 goto err_vdpa_register_driver; 1129 1130 return 0; 1131 1132err_vdpa_register_driver: 1133 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX); 1134err_alloc_chrdev: 1135 return r; 1136} 1137module_init(vhost_vdpa_init); 1138 1139static void __exit vhost_vdpa_exit(void) 1140{ 1141 vdpa_unregister_driver(&vhost_vdpa_driver); 1142 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX); 1143} 1144module_exit(vhost_vdpa_exit); 1145 1146MODULE_VERSION("0.0.1"); 1147MODULE_LICENSE("GPL v2"); 1148MODULE_AUTHOR("Intel Corporation"); 1149MODULE_DESCRIPTION("vDPA-based vhost backend for virtio"); 1150